Laboratory vessel



Aug. 2, 1960 A. R. DE LONG LABORATORY VESSEL Filed Oct. 10, 1957 R O m E W AZLE/V R. DeLdA/G LABORATORY VESSEL Allen R. De Long, Vineland, N.J., assignor to Bellco Glass, Incorporated, Vineland, N.J., a corporation of New Jersey Filed Oct. 10, 1957, Ser. No. 689,393

3 Claims. (Cl. 23-292) The present invention relates to a laboratory vessel and more particularly to a glass flask or vessel used in chemical and microbiological research and analytical laboratories.

Apparatus, such as flasks like Erlenmeyer flasks, beakers, etc., used for chemical manipulations and the like has always had a beaded uppermost edge. The function of such beaded uppermost edge is to facilitate the pouring of liquids and slurries, and to present a fire polished edge to the user of the apparatus so as to facilitate safe operation thereof.

However, experience has shown that a major cause of breakage of laboratory vessels is in the region of the uppermost edge by virtue of their beaded uppermost edge projecting outwardly and engaging other projections. For example, a study revealed that in an active chemical laboratory within a period of twelve weeks 41.6% of the conventional Erlenmeyer flasks used by such laboratory had broken necks. Breakage at the neck due to engagement of the beaded portion with other projections in use accounted for more breakage by far than any other single cause of breakage for Erlenmeyer flasks in that laboratory. It is to be noted that the breakage of Erlenmeyer flasks represents an economic loss not only in terms of the cost of replacing the broken flasks, but also in terms of thwarted experiments and loss of valuable reagents.

Breakage of laboratory glassware is prone to result in accidents to laboratory personnel from jagged edges, and losses due to injuries received from such accidents cannot, of course, be measured adequately by any economic indicator.

This invention has as an object the provision of a novel laboratory vessel.

This invention has as another object the provision of a laboratory vessel formed of glass which is less prone to breakage than other forms of laboratory vessels.

This invention has as yet another object the provision of a laboratory vessel which may be effectively used for chemical manipulations.

This invention has as yet another object the provision of a novel and useful Erlenmeyer flask.

Other objects will appear hereinafter.

For the purpose of illustrating the invention there is shown in the drawings a form which is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown.

Referring to the drawings wherein like reference characters refer to the like parts:

Figure l is a side elevation view, partly in section, revealing a preferred embodiment of the laboratory vessel of the present invention, such embodiment taking the form of an Erlenmeyer flask.

Figure 2 is a fragmentary plan view looking down from above of the Erlenmeyer flask shown in Figure 1.

Figure 3 is a diagrammatic view revealing the course States Patent lice followed when two conventional Erlenmeyer flasks are pushed against each other.

Figure 4 is a diagrammatic view similar to that of Figure 3 but revealing the course followed when two Erlenmeyer flasks of the present invention are pushed against each other.

Referring to the drawings and initially to Figures 1 and 2 the Erlenmeyer flask of the present invention is designated generally as 10. p

The Erlenmeyer flask of the present invention comprises an integral flask formed of transparent glass having a flat base 12, a generally conical body portion 14, a shoulder 16, a neck 18, and a mouth 20.

The lip 22' surrounding the mouth is tapered upwardly from the neck 18 at an included angle of about ten degrees. Thus, the thickness of the glass forming the neck 18 is uniform with the inside wall 24in of the neck 18 being generally parallel to the outside wall 26 of neck 18. Such thickness of the glass forming the neck 18 may be maintained throughout the body portion 14 and the base 12.

The inside wall 24 of the lip 22 is an extension of the inside wall 2411 of the neck 18 and is generally perpendicular to the base 12. However, the outside wall 28 of lip 22 projects angularly at the aforesaid angle of ten degrees to the inside wall 24 within any given vertical plane passing through the lip 22 and the diameter of the circle forming the mouth 20. The outside wall 28 extends upwardly a suflicient distance until the wall thickness of the glass forming the lip 22 is approximately twice that of the wall thickness of the neck 13 or the bottom portion of lip 22. Thus, the lip 22 projects upwardly until the thickness of glass intermediate inside wall 24 and outside wall 28 is twice the thickness of glass intermediate inside wall 24 and outside wall 28. When this point of approximate double thickness, designated as 30, is reached, the lip 22 is rounded off by means of arc 32 which extends to the mouth 20 of Erlenmeyer flask 10.

While an included angle intermediate the inside wall 24 and the outside wall 28 of lip 22 of ten degrees is to be preferred, about equally good results may be obtained when the angle is varied from this value by plus or minus three degrees. Thus, I have found that flasks in accordance with the present invention may be constructed in which the included angle between the inside wall 24 and the outside wall 28 of lip 22 is between seven and thirteen degrees, although as heretofore stated the angle of ten degrees is to be preferred.

The breakage encountered when conventional Erlen meyer flasks are pushed together is diagrammatically shown in Figure 3. Thus, conventional Erlenmeyer flasks 10a and 10a are shown being pushed together, namely the flask 10a engaging the flask 10a in the manner indicated by the arrow with the beaded edge 36 of flask 10a engaging the beaded edge 38 of the flask 10a. It will be noted that sliding disengagement between the beaded edge 36 of flask 10a and the beaded edge 38 of flask 10a is difficult, bordering upon the impossible since the beaded edge 38 functions as a stop-shoulder and resists the movement of the beaded edge 36. Breakage of one or both of the flasks 10a and 10a is likely from the engagement shown in Figure 3.

A comparative diagrammatic revelation of the engagement between two flasks of the present invention, designated respectively as 10 and 10', is shown in Figure 4. Thus, when the flask 10 engages the flask 10 in the manner shown by the arrow in Figure 4, the are 32 of lip 22' of flask 10' slides along the outside Wall 28 of the lip 22 of flask 10. There is no engagement between the lip 22' and the lip 22 at any stop-shoulder projection,

rather the are 32' engages the outside wall 28 with point contact, so that the friction between the engaging flasks 10' and 10 is minimal.

. When two hundred and eighty-eight Erlenmeyerflasks of the present invention divided evenly between flasks having a capacity of 250 milliliters and 500 milliliters were interspersed with two hundred and eighty-eight .conventional Erlenmeyer flasks evenly divided between similar sizes and were used interchangeably in the same chemical laboratory for a period of twelve weeks 41.6 percent of the conventional flasks had broken necks whereas but 2.6 percent of the flasks of the present invention had broken necks.

The present invention .may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specificationas indicating the scope of the invention.

I claim:

.1. An Erlenmeyer flask formed integrally of glass and including a flat base, a generally conical body portion, a generally tubular neck portion having a diameter less than the body portion for the entire height of said neck portion, a mouth from which the contents of the vessel are discharged at the top of said neck portion, said neck portion having a uniform internal diameter for its entire 4 height, the lip of said mouth being continuous and uninterrupted and tapering outwardly from bottom to top to a point below the uppermost surface of said mouth, the included angle intermediate the inside wall of the lip and the outside wall of the tapered portion of the lip being between about seven degrees to about thirteen degrees, and being arcuate from said point to the top surface of said mouth, with the topsurface of said mouth lying within a plane parallel to the base.

2. An Erlenmeyer flask in accordance with claim v1 in which thethickness of the glass forming the base, body portion and neck portion is uniform, and in which the thickness of the glass at the point below the mouth is about twice that of .the neck portion.

3. A laboratory vessel in accordance with claim 1 in which the included angle is about ten degrees.

References Cited in the file of this patent UNITED STATES PATENTS 1,072,330 Halverson Sept. 2, 1913 1,452,039 Gravell Apr. 17, 19.23

2,644,452 Brown July 7, 1953 FOREIGN PATENTS 246,051 Great Britain Jan. 21, 1926 

1. AN ERLENMEYER FLASK FORMED INTEGRALLY OF GLASS AND INCLUDING A FLAT BASE, A GENERALLY CONICAL BODY PORTION, A GENERALLY TUBULAR NECK PORTION HAVING A DIAMETER LESS THAN THE BODY PORTION FOR THE ENTIRE HEIGHT OF SAID NECK PORTION, A MOUTH FROM WHICH THE CONTENTS OF THE VESSEL ARE DISCHARGED AT THE TOP OF SAID NECK PORTION, SAID NECK PORTION HAVING A UNIFORM INTERNAL DIAMETER FOR ITS ENTIRE HEIGHT, THE LIP OF SAID MOUTH BEING CONTINUOUS AND UNINTERRUPTED AND TAPERING OUTWARDLY FROM BOTTOM TO TOP TO A POINT BELOW THE UPPERMOST SURFACE OF SAID MOUTH 